2 * viking -- GPS Data and Topo Analyzer, Explorer, and Manager
4 * Copyright (C) 2003-2005, Evan Battaglia <gtoevan@gmx.net>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
28 typedef struct _List {
33 /* a circular linked list, a pointer to the tail, and the tail points to the head */
34 /* this is so we can free the last */
35 static List *queue_tail = NULL;
36 static int queue_count = 0;
38 #define VIK_CONFIG_MAPCACHE_MAX_SIZE 50331648 /* 48 meggerbytes */
39 static guint32 queue_size = 0;
42 static GHashTable *cache = NULL;
44 #define HASHKEY_FORMAT_STRING "%d-%d-%d-%d-%d-%d-%.3f-%.3f"
45 #define HASHKEY_FORMAT_STRING_NOSHRINK_NOR_ALPHA "%d-%d-%d-%d-%d-"
47 void a_mapcache_init ()
49 cache = g_hash_table_new_full ( g_str_hash, g_str_equal, g_free, g_object_unref );
52 /* returns key from head, adds on newtailkey to tail. */
53 static gchar *list_shift_add_entry ( gchar *newtailkey )
55 gchar *oldheadkey = queue_tail->next->key;
56 queue_tail->next->key = newtailkey;
57 queue_tail = queue_tail->next;
61 static gchar *list_shift ()
63 gchar *oldheadkey = queue_tail->next->key;
64 List *oldhead = queue_tail->next;
65 queue_tail->next = queue_tail->next->next;
70 /* adds key to tail */
71 static void list_add_entry ( gchar *key )
73 List *newlist = g_malloc ( sizeof ( List ) );
76 newlist->next = queue_tail->next;
77 queue_tail->next = newlist;
80 newlist->next = newlist;
85 void a_mapcache_add ( GdkPixbuf *pixbuf, gint x, gint y, gint z, guint8 type, guint zoom, guint8 alpha, gdouble xshrinkfactor, gdouble yshrinkfactor )
87 gchar *key = g_strdup_printf ( HASHKEY_FORMAT_STRING, x, y, z, type, zoom, alpha, xshrinkfactor, yshrinkfactor );
90 /* FIXME: what if already exists? problem! */
91 g_hash_table_insert ( cache, key, pixbuf );
93 queue_size += gdk_pixbuf_get_rowstride(pixbuf) * gdk_pixbuf_get_height(pixbuf);
97 if ( queue_size > VIK_CONFIG_MAPCACHE_SIZE ) {
98 gchar *oldkey = list_shift_add_entry ( key );
99 GdkPixbuf *oldbuf = g_hash_table_lookup ( cache, oldkey );
100 queue_size -= gdk_pixbuf_get_rowstride(oldbuf) * gdk_pixbuf_get_height(oldbuf);
103 g_hash_table_remove ( cache, oldkey );
105 /* should delete BEFORE adding -- not really possible because don't know size,
106 * but you could guess size (only applic if add big file to full cache) */
109 while ( queue_size > VIK_CONFIG_MAPCACHE_SIZE &&
110 (queue_tail->next != queue_tail) ) { /* make sure there's more than one thing to delete */
111 oldkey = list_shift ();
112 oldbuf = g_hash_table_lookup ( cache, oldkey );
113 queue_size -= gdk_pixbuf_get_rowstride(oldbuf) * gdk_pixbuf_get_height(oldbuf);
116 g_hash_table_remove ( cache, oldkey );
119 /* chop off 'start' etc */
121 list_add_entry ( key );
122 /* business as usual */
125 if ( (++tmp == 100 )) { g_print("DEBUG: queue count=%d %ld\n", queue_count, queue_size ); tmp=0; }
128 GdkPixbuf *a_mapcache_get ( gint x, gint y, gint z, guint8 type, guint zoom, guint8 alpha, gdouble xshrinkfactor, gdouble yshrinkfactor )
131 g_snprintf ( key, sizeof(key), HASHKEY_FORMAT_STRING, x, y, z, type, zoom, alpha, xshrinkfactor, yshrinkfactor );
132 return g_hash_table_lookup ( cache, key );
135 void a_mapcache_remove_all_shrinkfactors ( guint16 x, guint16 y, guint16 z, guint8 type, guint zoom )
138 List *loop = queue_tail;
142 if ( queue_tail == NULL )
145 g_snprintf ( key, sizeof(key), HASHKEY_FORMAT_STRING_NOSHRINK_NOR_ALPHA, x, y, z, type, zoom );
148 /* TODO: check logic here */
151 if ( strncmp(tmp->key, key, len) == 0 )
153 g_hash_table_remove ( cache, tmp->key );
155 loop = queue_tail = NULL;
157 loop->next = tmp->next;
164 } while ( loop && (loop != queue_tail || tmp == NULL) );
166 /* loop thru list, looking for the one, compare first whatever chars */
168 g_hash_table_remove ( cache, key );
171 void a_mapcache_uninit ()
173 g_hash_table_destroy ( cache );